A typical so-called “upright” vacuum cleaner comprises a wheeled head assembly, which carries a fixed cleaner head, and an ‘upright’ body which can be reclined relative to the cleaner head and which includes a handle for maneuvering the vacuum cleaner across the floor. In use, a user grasps the handle and reclines the upright body until the handle is disposed at a convenient height for the user; the user can then roll the vacuum cleaner across the floor using the handle in order to pick up dust and other debris on the floor. The dust and debris is drawn in through a downward-facing suction inlet on the cleaner head by a motor-driven fan housed on-board the vacuum cleaner. From here, the dirt-laden air stream is then ducted under the fan-generated suction pressure to some sort of separating apparatus on board the vacuum cleaner, where dirt is separated from the air before the relatively clean air is then expelled back to the atmosphere. The separating apparatus may include a bag or cyclone, and may also include one or more filters for filtering very fine particulates from the air stream.
In some upright cleaners, the upright body comprises a relative large upright housing, typically formed from molded plastic, which incorporates the fan, the motor, the separating apparatus and any associated ducting: in these machines, the housing tends to be designed so that it is relatively tall and the handle is often conveniently provided on top of the housing, possibly as an integral-molded part of the housing.
Other upright vacuum cleaners do not incorporate large main housings, and in these machines the handle is often provided instead on a rigid, structural spine. This sort of “open” type of arrangement is shown in FIG. 1, which illustrates an upright vacuum cleaner a from the Dyson range of upright vacuum cleaners, currently sold under the model number DC15, in which a handle b is supported at the top end of a rigid, structural spine c running generally vertically up the rear of the machine a.
Historically, conventional wheeled upright vacuum cleaners were maneuvered across the floor by sequentially pushing and pulling the cleaner in straight lines, and the handle thus served primarily as a “push-pull” handle, with the main housing or rigid, structural spine acting to transmit push-pull forces down through the upright body and, ultimately, to the cleaner head. Many upright vacuum cleaners are currently still being designed to be maneuvered in this push-pull manner.
More recently, handles on some upright vacuum cleaners have been configured to rotate from side-to-side about the longitudinal axis of the upright body in order to provide some additional functionality for the cleaner. Thus, referring to FIG. 2, the handle b of the cleaner a forms part of a steering mechanism for improving maneuverability of the cleaner a; briefly, the handle b is rotatable from side to side about the longitudinal axis of the spine c as the cleaner a is being pushed or pulled, and the rotation of the handle b is transmitted via the spine c to some intermediate part of the steering mechanism which is operably connected to a steering yoke configured to steer the cleaner head to the left or right accordingly. This sort of steering mechanism is described in more detail in European Patent No. EP1526796.
It is often desirable to clean above the level of a floor. For example, it may be desirable to clean shelving, stairs or the upper corners of a room. For this purpose, many upright vacuum cleaners are now additionally provided with a suction wand which is connected to a suction inlet on the vacuum cleaner by a flexible hose, allowing the vacuum cleaner to be operated as desired in the manner of a “cylinder” (or “canister”) cleaner, rather than in the manner of an “upright” cleaner. For convenience, the wand is normally releasably stored on-board the vacuum cleaner, and the hose itself is retractable for reducing the corresponding storage length of the hose on the vacuum cleaner.
In the absence of a relatively large main housing, the structural spine in an “open” type of upright vacuum cleaner typically also acts as a mounting support for the separating apparatus. Thus, referring again to FIG. 1, the vacuum cleaner a comprises a so-called “cyclone pack” d which is a removable component seated on a mounting platform e at the front of the cleaner a and secured in place by means of a manual release catch f which engages the spine c. The cyclone pack d incorporates a multi-stage cyclonic separation system g, along with associated inlet and outlet ducting (e.g. inlet duct h), which feeds a generally cylindrical dust-collecting bin i. During use of the cleaner a the dust collecting bin i gradually fills with dust and debris separated in the separation system g and when it is desired to empty the dust collecting bin i, the entire cyclone pack d is released by manually depressing the catch f and then removed in its entirety from the cleaner a. Once the cyclone pack d has been removed, the bin i can then sequentially be detached from the remainder of the cyclone pack d for emptying through the top of the dust collecting bin i, or the bottom of the dust collecting bin i may be provided with a trap-door (not shown), which may be opened using the same catch f.
A carry handle j is provided on top of the cyclone pack d for handling the cyclone pack d, and this same carry handle j can also be used to lift and carry the cleaner a when the cyclone pack d is secured on board the cleaner a. The carry handle j is located close to the catch f for convenience when removing the cyclone pack d, and so to prevent accidental depression of the catch f as a user lifts the cleaner a using the carry handle j, the catch f is additionally configured to allow the entire cyclone pack d to slide upwardly relative to the spine c to obstruct operation of the catch f. This type of catch arrangement is described in more detail in GB Patent No. GB2416483.
The main housing or the structural spine is designed to have sufficient flexural and torsional stiffness to provide a stable support for the handle, especially during use of the handle to maneuver the cleaner head across a floor. Torsional stiffness is particularly desirable where the structural spine or main housing of the upright body is required to transmit rotation of the handle from side to side about a longitudinal axis of the upright body to some intermediate part of a steering mechanism.
It is an object of the present invention to seek to provide an improved upright cleaning appliance.